Problem 111
\(2 \mathrm{~g}\) of aluminium is treated separately with excess of dilute \(\mathrm{H}_{2} \mathrm{SO}_{4}\) and excess of \(\mathrm{NaOH}\). The ratio of the volumes of hydrogen evolved is (a) \(1: 1\) (b) \(1: 2\) (c) \(2: 1\) (d) \(2: 3\)
Problem 112
Which of the following reactions written here are correct? (1) \(\mathrm{B}+\mathrm{NaOH} \longrightarrow 2 \mathrm{Na}_{3} \mathrm{BO}_{3}+\mathrm{H}_{2}\) (2) \(\mathrm{P}_{4}+\mathrm{NaOH}+\mathrm{H}_{2} \mathrm{O} \longrightarrow \mathrm{NaH}_{2} \mathrm{PO}_{2}+\mathrm{PH}_{3}\) (3) \(\mathrm{S}+\mathrm{NaOH} \longrightarrow \mathrm{Na}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}+\mathrm{Na}_{2} \mathrm{~S}+\mathrm{H}_{2} \mathrm{O}\) (a) 1 only (b) 3 only (c) 2 and 3 (d) 1,2 and 3
Problem 113
Match the following: List I List II 1\. Sorel's cement (i) \(\mathrm{MgCl}_{2}\) 2\. Albite (ii) \(\mathrm{MgO}\) 3\. A salt of carnalite (iii) \(\mathrm{NaAlSi}_{3} \mathrm{O}_{8}\) 4\. Glauber's salt (iv) \(\mathrm{Na}_{2} \mathrm{SO}_{4} \cdot 10 \mathrm{H}_{2} \mathrm{O}\) The correct matching is: 1 2 \(3 \quad 4\) (a) (ii) (iii) (iv) (i) (b) (iv) (ii) (ii) (i) (c) (iii) (ii) (i) (iv) (d) (ii) (iii) (i) (iv)
Problem 114
Aluminium is more reactive than iron because its standard reduction potential is higher. Still aluminium is less easily corrdoed than iron because (a) Al reacts with atmospheric carbon dioxide to form a self protective layer of \(\mathrm{Al}_{2} \mathrm{O}_{3}\) (b) it has higher reducing power and forms a self protective layer of \(\mathrm{Al}_{2} \mathrm{O}_{3}\) (c) it has higher reducing power and does not react with oxygen so easily (d) both (a) and (b)
Problem 115
Some large white transparent crystals are left out in a bowl for several days. They are then observed to have changed their form into white powder. The crystals may have been of (a) calcium oxide (b) sodium carbonate (c) ammonium chloride (d) sodium chloride
Problem 117
A solution when diluted with water and boiled, gives a white precipitate. On addition of excess of \(\mathrm{NH}_{4} \mathrm{Cl} /\) \(\mathrm{NH}_{4} \mathrm{OH}\), the volume of precipitate decreases, leaving behind a white gelatinous precipitate. Identify the precipitate which dissolves in \(\mathrm{NH}_{4} \mathrm{OH} / \mathrm{NH}_{4} \mathrm{Cl}\). (a) \(\mathrm{Al}(\mathrm{OH})_{3}\) (b) \(\mathrm{Ca}(\mathrm{OH})_{2}\) (c) \(\mathrm{Mg}(\mathrm{OH})_{2}\) (d) \(\mathrm{Zn}(\mathrm{OH})_{2}\)
Problem 119
\(1.04 \mathrm{~g}\) of bleaching powder was made into a paste with water and then the volume was made upto 200 ml. \(25 \mathrm{ml}\) of this solution was found to oxidize \(13.4\) \(\mathrm{ml}\) of a standard solution of arsenic containing \(4.3 \mathrm{~g}\) \(\mathrm{Al}_{2} \mathrm{O}_{3}\) per litre. Find the percentage available chlorine in the sample. (a) \(31.7 \%\) (b) \(36.7 \%\) (c) \(41.7 \%\) (d) \(63.6 \%\)
Problem 120
A white, water-insoluble solid \((\mathrm{A})\), is attacked by an acid, liberating a colourless, odourless gas (B), leaving a clear solution (C). The solution (C) gives a white precipitate (D) on addition of dilute \(\mathrm{H}_{2} \mathrm{SO}_{4},(\mathrm{C})\) gives a yellow precipitate (E) on addition of \(\mathrm{K}_{2} \mathrm{CrO}_{4}\) solution. Gas (B) bubbled through a suspension of \(\mathrm{CaCO}_{3}\) causesdis solution of that compound. Identify (E). (a) \(\mathrm{CaCrO}_{4}\) (b) \(\mathrm{BaCr}_{2} \mathrm{O}_{7}\) (c) \(\mathrm{BaCrO}_{4}\) (d) none of these
Problem 121
The aqueous solution of an inorganic compound \((\mathrm{X})\), gives a white precipitate with \(\mathrm{NH}_{4} \mathrm{OH}\), which does not dissolve in excess of \(\mathrm{NH}_{4} \mathrm{OH}\). This aqueous solution also gives white precipitate with \(\mathrm{AgNO}_{3}\) and the precipitate is soluble in dilute \(\mathrm{HNO}_{3} .\) Here ( \(\mathrm{X}\) ) is (a) \(\mathrm{AlCl}_{3}\) (b) \(\mathrm{AlBr}_{3}\) (c) AIN (d) \(\mathrm{Al}_{2}\left(\mathrm{SO}_{4}\right)_{3}\)
Problem 122
Match the following: \(\begin{array}{ll}\text { List I } & \text { List II }\end{array}\) 1\. efflorescent (i) \(\mathrm{NaOH}\) 2\. deliquescent (ii) \(\mathrm{KOH}\) 3\. fusion mixture (iii) \(\mathrm{Na}_{2} \mathrm{CO}_{3}\) and \(\mathrm{K}_{2} \mathrm{CO}_{3}\) 4\. washing soda (iv) \(\mathrm{Na}_{2} \mathrm{CO}_{3} \cdot 10 \mathrm{H}_{2} \mathrm{O}\) The correct matching is 1 2 3 4 (a) (ii) (i) (iv) (iii) (b) (i) (ii) (iii) (iv) (c) (ii) (i) (iii) (iv) (d) (i) (iii) (iv) (ii)
